I have a /99 Ranger 3.0 Auto 2 WD. Check engine light on with a code P0401 EGR insufficient flow. Anyone have a idea what to replace first. EVR solenoid ( voltage and resistance seem to check ok). EGR valve is original, removed and cleaned as good as I can get it. Replaced with new gasket. DP sensor voltage ok, also original metal type. I understand the new one is plastic. Cleared code twice ( negative battery terminal removed and replaced ) and after driving for awhile light comes back on. Any Help Would Be Appreciated Thanks Van

 

Welcome to FTE!
There were some posts about the tube from the exhaust to the EGR getting clogged & restricting flow. This may or may not be the problem you are having.
Try using the search feature and type in "P0401" using quotation marks. The return will have a wide variety of info that you'll have to pick through.
Also, post this question in the Ranger & B-Series forum. There are several resident experts there that can walk you through all the needed checks & repairs for any problem you may have.
There is a "Technical Information" sticky thread at the top of the Ranger board that has info on codes & lots of other frequent Ranger repairs.
Hang in there!
AL.